<template>
        <!-- 输入框 -->
<header class="header">
    <h1>小黑记事本</h1>
    <input @keyup.enter="handleAdd"
    v-model="todoName" placeholder="请输入任务" class="new-todo" />
    <button @click="handleAdd" class="add">添加任务</button>
  </header>
</template>

<script>
export default {
  data (){
return {
  todoName: ''
}
},
methods: {
handleAdd () {
  if(this.todoName.trim() === '') {
    alert('任务名称不能为空')
    return
  }
  this.$emit('add', this.todoName)
  this.todoName = ''
}
}
}
</script>

<style>

</style>
